基于不同设计方法的沥青稳定碎石弯曲疲劳特性

Bending-Fatigue Performance of Asphalt Treatment Based on Different Design Method

研究采用三点弯曲疲劳试验对沥青稳定碎石进行疲劳性能研究,分析不同设计方法下不同公称最大粒径对混合料疲劳性能的影响。试验结果表明,采用Superpave法设计的混合料抗疲劳性能最好,但对应力的变化较为敏感;依据《规范》推荐的级配中值混合料抗疲劳特性与采用贝雷法设计的混合料的抗疲劳特性相当,但采用贝雷法设计的混合料对荷载应力的敏感度最小;粒径较小、细集料含量较高、均匀密实的混合料抗疲劳性能较好。设计方法对n值和k值有显著性影响,而公称最大粒径及其与设计方法的交互作用对n值和k值影响较小。

Three-point bending fatigue test is used to study the anti-fatigue performance of asphalt treatment base and analyze the effect of the different design method and maximum normal size on fatigue performance. The results show that the fatigue performance of asphalt mixture is better designing by Superpave method, but it is sensitive to stress. The fatigue performance of the intermediate of standard recommend is as well as that of asphalt mixture design by Baley. But the mixture designing by Babey is not sensitive to stress. The anti-fatigue performance of mixture that are small in size, higher in fine aggregate content, uniform and close-grained is well. The design procedures have significant effect on n and k value, maximum normal size and reciprocity between maximum normal size and design method have small influ- ence.